Abstract: We propose an individually randomized Early Childhood Caries (ECC) controlled prevention trial to test the impact of micro-incentives (combined with infant oral care and tiered digital Anticipatory Guidance) on increasing attendance of regular oral care visits and parental adoption of ECC prevention behaviors in an at- risk population from Early Head Starts and Women and Infant and Children (WIC) programs in Los Angeles County. Previous studies have shown that mere health education is insufficient to make a lasting impact on health behaviors. Despite growing evidence that small, cost-effective interventions that leverage theories and insights from behavioral economics, which incorporate elements of cognitive psychology to understanding health behaviors, can promote behavior change, none have been applied to oral health interventions. Our proposed behavioral economics theory-driven study explores the use of micro-incentive mechanisms to motivate adoption of ECC prevention habits, and, through a phased approach, will identify the most effective micro-incentive and test its impact and cost-effectiveness. The target population of the trial is underserved Los Angeles Country children between 0 to 3 years old at enrollment and their caregivers. Both genders will be recruited. Eligible children must meet the following criteria: (1) Age 0-3 years; (2) Family geographic stability (greater Los Angeles residence); (3) Parental informed consent in English or Spanish; (4) Children registered as participants at EHS or WIC; and (5) Children at high caries risk. During the pilot phase (UH2), the study will explore the feasibility, acceptability, and appropriateness of different modalities of structuring micro-incentives and determine whether the community finds cash, noncash equivalent-value gift card/voucher, or lottery payouts acceptable through qualitative methods (focus group) and quantitative measures (surveys). The incentive size and modality likely to be effective will be used to design the UH3 phase trial. In addition, the pilot study will validate primary outcome measures, such as toothbrushing adherence and timely attendance to office visits, and will inform identification of secondary outcome measures, such as change in parental/caregiver behaviors for oral health promotion and disease management. The UH3 phase will randomize individual parents/caregivers in up to five Los Angeles County EHS and WIC centers to micro-incentives (as determined in the pilot phase) or no incentives for behavioral change and measure ECC preventive behaviors and child's oral health. The goal is to estimate the cost effectiveness and return on investment of micro-incentives in improving parent/caregiver behaviors and children's oral health.